Log Splitter Pressure

[J_J]

I have to correct some of my figures, as I was computing for a 24 in log.

With a 16 in cyl, it will take about 26.6 sec to fully extend the cyl.

 

[WildArkie]

The outside diameter of the cylinder is 6 inches and the outside diameter of the rod/shaft is 3.5 inches. The travel length is about 16 inches.

I will adjust and measure the rpm and test the pump.

 

[shansen]

The valve in the pictures is 1970's or earlier vintage. The relief was correctly identified. The valve is not cracked, the slot in the adjusting screw and valve body are very corroded. Also, the valve in the ebay link is a 3-postion, 4-way, spring centered valve, probably mid 80's vintage. Our C-908 valve is the log splitter valve we make. The plumbing and mounting connections will be very, very close to the valve in these pictures. I have not read this entire thread, but just wanted to point out a few things regarding our products. The C-908 available at our website: Hydraulic Cylinders
I would state the price here but I don't know if that is allowed.
Steve Hansen
Applications Engineer
Energy Manufacturing Co., Inc.
(319)-465-3537 X-402
(319)-465-5279 FAX
shansen@energymfg.com

 

[Haywire]

The outside diameter of the cylinder is 6 inches.

Figuring 1/4" wall thickness, it's probably a 5.5" cylinder.. That's a pretty big one. If you get this thing up to 3000psi, I expect you'll never run up against anything that it won't split.

Ian

 

[WildArkie]

Well to give an update I used a punch and hammer to turn the pressure relief screw in. After a full turn it loosened up and I am able to turn it with a screwdriver now. I turned the engine throttle down to lower the rpm's and the engine stalled at about 1500 psi.

I turned the throttle back up and played with the PR so the gauge will show 2000 to 2500 psi when it is fully extended or retracted. Problem is when it hits this pressure now it kills the engine. No bogging just stops it.

I am able to split the wood that I was not able to before. I split several pieces. But, when it did get a tough piece and the pressure went to around 2500 it killed it without warning (other than psi). I would start the engine again and either reposition the wood piece or try to push again. Sometimes it would split the second time and sometimes just kill the engine again.

So, is the pressure relief not working stopping the fluid to return to the tank and killing the engine or is the engine just weak and dying under pressure. It either boggs down or dies wherever the pressure relief valve is set at, 800 or 2500. One other thing, I turned the pressure down to about 500 psi and the engine still started to bogg down until I released the valve handle.

 

[glastron23]

Wild... your engine is just running out of horse power to keep the pump turning,,,, when you stall the hydraulics you need about 2 hp per gallon of pump flow at 2500 psi. this is were the 2 stage pumps come in real handy, it allows lower HP engines to work with a high flow/low pressure(for fast extend/retract) and low flow/high pressure (for tough splitting) and keep the engine from stalling. Jim

 

[J_J]

If you say that your pump went to 2500 psi, and stalled, that is what is supposed to happen. At max engine rpm, you are pumping 8.14 GPM, and the pump, using cyl resistance, is trying to produce 2500 psi. It needs about 14 HP at that rpm and pressure, so now you have the answer.

The engine to support that pump should be about 14 HP. So at max rpm on your 9 HP engine, you are running out of HP. The system is just not matched.

You need another engine, and new valve.

 

[WildArkie]

That is not what I began this discussion wanting to hear. I was thinking I might have to get a two stage pump and maybe a valve as a added bonus to have the detent feature if I could not get everything lined out. Now it looks like I have to do the biggie, engine. This will take some time to look and find something without buying new. I guess that is what I get for getting the splitter free and expecting to it to be easy.

Since my single stage pump increases the gpm with higher rpms will the two stage pump limit the high pressure to 4 gpm at 3600 rpm allowing a lower HP engine? I should say I want to know if the higher rpms will make a two stage pump do 6 gpm, on the high pressure, creating the same HP shortage for me.

https://www.surpluscenter.com/item.asp?item=9-1390&catname=hydraulic

 

[Haywire]

You don't have to do the engine... it's either the engine, or a pump that the current engine will support... think of it as a see-saw. It needs to be balanced. You can take some off one side or add to the other.

Ian

Edit: this one requires at least 8hp, this one only requires 6hp if your engine is a little tired and both of them will over double your ram speed.

 

[J_J]

That is not what I began this discussion wanting to hear. I was thinking I might have to get a two stage pump and maybe a valve as a added bonus to have the detent feature if I could not get everything lined out. Now it looks like I have to do the biggie, engine. This will take some time to look and find something without buying new. I guess that is what I get for getting the splitter free and expecting to it to be easy.

Since my single stage pump increases the gpm with higher rpms will the two stage pump limit the high pressure to 4 gpm at 3600 rpm allowing a lower HP engine? I should say I want to know if the higher rpms will make a two stage pump do 6 gpm, on the high pressure, creating the same HP shortage for me.

https://www.surpluscenter.com/item.asp?item=9-1390&catname=hydraulic

If you like your engine, then this two stage pump will work.

https://www.surpluscenter.com/item.asp?item=9-1390&catname=hydraulic

How well do you like your valve?

There are limits as to what one can do, and sometimes things can be manipulated, but in general, rules are rules.

We are simply trying to keep you from making mistakes, and wasting money.